Crash course in running an art gallery (Boston)

Last month, a property owner in Boston's Beacon Hill neighborhood asked me to turn a small (400 sq ft) ground floor office space into an art gallery, which I would also run. Today, we spent a long time looking at the space (on W. Cedar St nr Cambridge St), as well as discussing the vision, expenses, commission, revenue, insurance, staffing/interns, hours, maintenance, marketing, and more. By the end of our conversation I felt comfortable and was excited to work on this project outside of my full time job.

That said, although I have experience working with and managing artists, I don't have any experience running a commercial art gallery. If anyone has advice on pitfalls, opportunities, and other things to consider, I'd appreciate hearing it. We're looking at a mid-Sept launch, so there's a small window of time during which I can tackle my learning curve.